Because average human nature is to be mean. A small outlier fraction of us are not.
Just like average human nature is to be incurious and unthinking and mostly stupid. A small outlier fraction of us are not.
For a long time the curious smart folks ran the economy to their advantage. And to some deree ran politics to their advantage. Which means their greater influence disguised their lesser numbers.
When the mean and stupid people get in power, we see how a world made in their image, not your or my image, works. It works badly and violently and thuggishly. And those folks are very comfortable in that milieu while being very uncomfortable in ours.